I got a 3 row one off eBay, has the lower union for the matrix return and was really happy with the quality - it's survived cooling the 13BT with no problems at all. Can't remember the seller though so not very helpful.

Finally got my radiator rebuilt, I've had it recored with a twin core so that should help with the cooling problem I was having, also the old single core was mostly blocked.
When removing the rad I noticed a threaded plug in the bottom left hand corner of the rad facing the engine, anyone know what this is for ?
Now all I need to do is have a good clean up respray the rad surround and refit ready to tax in May.

I've spent the last half hour trying to add photos now pissed off .... So sorry no pics